Platformer GDD

Game Title: Moyai
Game Overview
Game Type: 3D platformer
Backstory and Plot:
You control an unnamed statue that must return to its original position somewhere on the island. Avoid or crush enemies in your path. Collect gems scattered across the level to improve your score.
Characters:
You: You play as a statue.
Enemies: Distinct rock creatures that will attack you for your gems.
NPCs: There are statue NPCs across the island, which may give hints to the player.
Level:
A single level.
An island setting features grass plains, mountains, small forests and beaches. Water surrounds the island chain on all sides. There will be an invisible barrier preventing players from wandering too far out to sea. Also there may be deep areas of water which will drown the player, making them take damage over time. There are areas of shallow water that can be moved through.
Visual Style:
Natural visuals.
Audio Style:
Music that evokes an island feeling.

Level Overview
About:
You control an unnamed statue that must return to its original position somewhere on the island. Avoid or crush enemies in your path. Collect gems scattered across the level to improve your score.
Characters:
Only notable character is the player character, an unnamed Easter Island statue head.
Location/setting,time period, mood, lighting, weather conditions:
The location is an island setting.
Time of day: Noon or sunset
Light mood.
Fairly bright lighting.
Clear weather and skies.
Structures, buildings, objects, and decoration
Small objects such as rocks and trees
Important places, events, encounters, hazards
Important place: Cliff edge.
Enemies will be scattered across the level
Deep bodies of water will also exist.
Start and End:
The player starts on the coast of the island. The statue’s desired location is on the edge of a cliff. The level will end once the player reaches their destination.
Scale:
Large enough for the player to collect 20 gems.
Length:
5-10 minutes.

Map Mockup is provided

Landscape Reference Images, and Unity Assets are included in the post. Links are also included below in order
https://pixabay.com/images/search/island/
https://unsplash.com/s/photos/island
https://www.istockphoto.com/photos/easter-island
https://assetstore.unity.com/packages/3d/props/bronze-bear-statue-65904
https://assetstore.unity.com/packages/3d/characters/humanoids/fantasy/giant-monster-model-golem-278960
https://assetstore.unity.com/packages/package/228680
https://assetstore.unity.com/packages/2d/textures-materials/water/stylize-water-texture-153577
https://assetstore.unity.com/packages/3d/environments/koi-pixel-rocks-and-trees-286469